This device is designed firstly for use by do-it-yourself enthusiasts and amateur gardeners, for example, and also for professionals such as brick layers, tilers, electricians, carpenters, roofers, gardeners, landscape artists, etc.
In the context of their activities, these persons are frequently confronted with the problem that consists of materialising limits that are perpendicular to other existing or future limits, for example for the construction of a house, a veranda, a fence, plantation, structure, etc.
For individuals, “bricklayer” right angle measuring devices are available composed of two flat bars welded together forming an angle of 90 degrees to each other. These right angle measuring devices do not resist shocks and are only precise for small dimensions (less than 2 meters).
Amateur gardeners cannot make good use of this instrument which is not suitable for surfaces such as lawns, gardens, and alleys. Without appropriate means, these persons usually work “by eye”.
Professionals have three solutions:
1) The bricklayer's right angle measuring device, with the limits and disadvantages mentioned above.
2) The “3, 4, 5” method which is nothing more than application of Pythagoras's principle of a right angled triangle, by which the square of the hypotenuse is equal to the sum of the squares of the other two sides (3×3+4×4=5×5).
This process has the advantage of excellent precision, but its use is old-fashioned, painstaking, complicated and requires the participation of two persons together with a measuring instrument (ten-meters rule). Furthermore, the fact that three precise measurements have to be made, frequently under poor conditions, introduces a risk of error.
3) The theodolite, a very precise but very expensive and fragile instrument that requires difficult and complex operations for use.
These known means are not adapted to the demand and to needs. Thus, plumbers have to compensate for out-of-square distances of several centimeters over the width of a bath, and tilers frequently observe differences of more than 10 cm in a single room, even in new constructions.
Therefore, the purpose of the invention is to divulge a device that solves the problem simply, quickly, with excellent precision even over long distances (several tens of meters) without any complex or expensive means and without any risk of error.